Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm fairly new to the whole UNIX / command shell sort of stuff, so I apologize for any ignorance for something I am not aware of. And by new, I mean extremely new.

I was confused by how to change a file's permissions back to the way they were before. I have the output for the file's permissions from "ls -l filename" before they were changed, and I am just trying to revert them back to the way they were.

I need to make the file ("install.php") to have the following permissions (as given to me by "ls -l install.php"):

rw-r--r-- 1 1000 1000 620

What would be the proper syntax of the chmod command to make this file have the above permissions? Thanks in advance!

share|improve this question
Just type man chmod and it will show you How to use the command – 50-3 Sep 18 '13 at 22:08
up vote 3 down vote accepted

see this -

Its very simple binary first 3 rwx is for the owner - 110 a 6 second 3 rwx is for group - 100 - a 4 third 3 rwx is for other - 100 a 4

in your scenario chmod 644 filename

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.